Oil-well heater



.lune 3, 1930. w. c. PASLEY `OIL WELL HEATER Filed Jan. 2, 1929 v INVENTOR. Emy@ l l l l l a f l z\\ A TTORNEY.

Patented June 3? 1930 PATaNT -oFFlcE y wooDsoN c. PASLEY, oF'wIoHITArALLs, 'razas OIL-WELL HEATER Appncauon ned January 2,1929. serial no. 329,840.

high temperature thereby eliminatingbreakage of the oil pipes and other elements of the la equipment.v

Another objet of the invention resides in the provision of a means toindicate at all times the correct temperature of the heating device While in the Well in order that the heat 2@ may be regulated by rheostatic control from the surface to prevent over heating the sands Where theuid is prevalent, .as in some instances/excess heating Will cause the Walls of the Well to crystallize and harden and conses 25 quently will very often render the Well non-v productive and useless.

Still another object of the invention is inanifest in its simplicity of construction making it possible to produce a device ot the character or extreme usefulness at a nominal cost Having thus recited the numerous objects and novel features of the invention, a further description may be had by reference tothe appended drawings in which 335 Figure 1 is an elevational vienr in cross section or the invention Withinthe contines ot the oil well casing. Figure 2 represents'a top vievs7 in cross section taken on line 2 2 in Figure 3 showing 40 the expansion joint inthe base of the invention.

Figure 3 is an elevational view showing the thermocouple, and

Figure 4 is an elevational view in cross seo/-y 45 tion showing the expansion joint in detail.

Paraiin deposits in the pores of the oil sands are common especially in oil Wells that have been producing for some time and at certain stages in the accumulation of these de 50 posits it is diicult to pump the oil to the sur-4 ace, due to'the congealed condition of the paraiin.

Itis obvious, that means can be provided to melt these parain deposits and open the pores of the oil sand in order'that the well can '55 resume its normal production, and this urpose will be satisfactorily served by use o the invention herein described.

Heaters of the ordinary type when placed in use might cause serious damage to the other @o equipment and also to the Well itself due to the expansion of metal when submitted to severe heat and to the crystallizing and hardening of the underground Walls or an oil well underv high temperature thereby render- @5 ing the oil Well non-productive and useless. To those versed in t-he art, it is a Well `known fact that when oil is heated to approximate- 'ly 300 degrees Fahrenheit it `will carbonize and`harden. llt is, therefore the purpose of a@ this invention to prevent this Proceeding. more in detail vvith the description, reference is again made to the drawings and to the character i which indicates the barrel of the invention having an apertured a@ head 2y through which the oil tubing 3 is passed extending downward through the expansion joint 4i which consists ot tvvo conical shapedl castings 5 at the top and bottoni of a circular band or heat conducting composition ti pret'- g@ erahly of rubber and metal cllippings9 which will absorb the necessary expansion vvhich ordinarily accompanies severe heat.

A coil 7 `Wound with nichrorne vvire insulate ed with mica or other suitable insulation and @5 being capable of surcient resistance to produce heat commensurate with the amount or voltage passed through the coil is provided to surround the pipe 3 through the center o ,the barrel l and is grounded at the bottom no oit the barrel to the pipe 3 and connected at its upper end through cable 8 to Wire 9 thence to the secondary winding ot the transformer 10. The other 'end ont transformer 10 being connected to the upper portion ot the pipe 3 o5 by a Wire leading through an ammeter 11 thus completing the circuit through the v transformer and heating unit b means o the pipe 3. The current dowing t' rough the heating unit is controlled by a rheostat 12 connected 100 in series with the transformerlO across the normal supply line, thus providing a means for varying the flow* of current as desired.

Due to the necessity vof preventing overheat- 5 ing of the heating coil 7 a thermocouple 13 consisting of semiconcaves of disslmilar metals such as a platinum-irridium combina tion, capable of generating a thermo-electric current, are attached by meansl of bolts or screws to the lower portion cf the barrel 1 of the invention and are connected to the pyrom'eter 14 through the wires 15 and 16.

In operation the current is turned on and regulated through the transformer 10 and the heater coil 7 by the rheostat 12, the ammeter 11 registerin the amount of amperage passing through t e coil 7,v and when la temperature of approiimately 250 degrees Fahrenheit is .indicated by the pyrometer 14 the current is 420 reduced in order that this temperature can be maintained as long as desired.

vIt is not intended however, to show in these specifications that it is necessary to maintain any predetermined degree of heat in 27s-all casesas climatic and soil conditions wary.

It is not intended to limit the invention as it is obvious that certain modifications in the above specification can be made and such modifications as are considered Within the so scope and meaning of the appended claim.

What is claimed is In combination with a strin of tubing in an oil well, a casing disposed aIiout said tubingand spaced therefrom and having its upperend closed, a heating unit within said casing, an expansion unit within said cas-i ing beneath said heating unit, said expansion unit comprising a pair of spaced conically shaped collars engaging the circumfer- 40 ential wall of the tubing and casing, andheat insulating means disposed between said collars and engaging the circumferential wall of the tubing Aand casing and filling the space between said walls and said collars.

In testimony whereof I aiix my Signature.

WOODSON C. PASLEY. 

